The present disclosure relates to a mechanical seal arrangement, and more particularly to a tandem seal arrangement with reverse flow secondary seal.
Mechanical seal arrangements are used in a wide variety of processes to prevent fluid leakage such as from turbomachinery which is used to transport a process fluid. The turbomachinery often includes a pump or compressor, which includes a shaft driven impeller. The shaft is driven by a motor either directly or indirectly through a gearbox such that the shaft extends from the motor or gearbox to the turbomachinery.
Conventional mechanical seal arrangements, although effective, may permit a very small percentage of lubricant to leak from the gearbox to atmosphere. Tandem process seal arrangements also may permit a very small percentage of process fluid to leak from the turbomachinery to atmosphere (FIG. 1). This may, in some instances, have an environmental impact.